(Not Applicable)
(Not Applicable)
The present invention relates generally to fluid valves, and more particularly to diaphragm type valves used in sterile access and GMP orientations.
A diaphragm type main flow valve includes a valve housing body. The valve housing body has an inlet port which connects with an upstream passage which extends into the valve housing body. The valve housing body further has a downstream passage which is aligned with the upstream passage. The downstream passage extends to an outlet port. A main flow valve mounting surface is formed upon the valve housing body. A main flow valve weir is formed in the valve housing body adjacent the main flow valve mounting surface, and separates the upstream and downstream passages. A diaphragm type valve housing may be mounted upon the main flow valve mounting surface, with a diaphragm being configured to engage the main flow valve weir. Actuation of the diaphragm against the main flow valve weir prevents fluid flow between the upstream and downstream passages thereby closing the valve. As such, with the diaphragm in a closed position, fluid flow from the upstream sampling passage is prevented from entering into the downstream passage. With the diaphragm in an open position, the downstream passage is in fluid communication with the upstream passage for passage of fluid flow from the upstream sampling passage. In this regard, the main flow valve is intended to control fluid flow in a product main flow path to which it is attached.
In order to obtain product samples from such product main flow path, the main flow valve may have a separate sampling valve attached to it. Such valve may additionally function as a purge valve. The sampling valve may have a sampling valve housing body which has a primary passage which is in fluid communication with the downstream passage of the main flow valve housing body. In this regard, the primary passage may be connected, typically welded, to the downstream passage through intermediate piping. This inherently creates a dead-leg within the intermediate piping. The sampling valve housing body further has a secondary passage which terminates at a sampling port. A sampling valve mounting surface is formed upon the sampling valve housing body. A sampling valve weir is formed in the sampling valve housing body adjacent the sampling valve mounting surface, and separates the primary and secondary passages. A diaphragm type valve housing may be mounted upon the sampling valve mounting surface, with a diaphragm being configured to engage the sampling valve weir.
In this regard, with the diaphragm of the main flow valve in the open position, fluid flow is allowed to pass into the downstream passage an into the primary passage of the sampling valve housing body. With the sampling valve in an open position, fluid flow is allowed to further pass over the sampling weir, into the secondary passage, and out the sampling port.
As mentioned above, such main flow and attached sampling valves may be used for sampling fluid product from a main flow path. These valve arrangements have application in a wide range of fluid handling systems, such as those for pharmaceutical, biotech processing, food and beverage, and cosmetic and consumer products applications. Such applications are typically subject to strict governmental regulations and industry practices and procedures. Cleanliness and sterility of the downstream passage of the main flow valve housing body and the attached primary passage of the sampling valve housing body. In this regard, efficient gravitational drainage of the downstream passage and the intersecting primary passage is of particular concern.
The interior drainage design characteristics of the downstream and primary passages are dependent upon the orientation of the overall main flow/sampling valve arrangement is to be installed. Those main flow/sampling valve arrangements which are designed to be utilized with the upstream and downstream passages of the main flow valve housing body arranged horizontally are referred to as sterile access valves. Those main flow/sampling valve arrangements which are designed to be utilized with the upstream and downstream passages of the main flow valve housing body arranged vertically are referred to as GMP (good manufacturing practices) valves.
A problem encountered with such sterile access valves and GMP valves is that inherent in their current designs, they cannot be use interchangeably. In this regard, while contemporary sterile access valves are designed to have efficient drainage characteristics when utilized in their intended horizontal configuration, use of such sterile access valves in a vertical orientation results in entrapped fluids or otherwise non-draining regions. Similarly, use of such GMP valves in a horizontal orientation results in entrapped fluids or otherwise non-draining regions. As such, those responsible for maintain fluid product handling systems must typically must carry dedicated inventories of both sterile access and GMP valves. However, as such valves perform the same function utilization of two different valve designs is inefficient. Another problem associated with the above described valve arrangements is that the main flow valve and the sampling (or purge) valve are separate structures. Further mentioned above intermediate piping must typically be welded to both valve structures. This inherently creates a dead-leg within the intermediate piping. Accordingly, there is a need in the art for an improved main flow valve and sampling (purge) valve arrangement in comparison to the prior art.
In accordance with an embodiment of the present invention, an integral sterile access/GMP valve housing which includes an integrally formed valve housing block. The valve housing further includes main flow and sampling valve mounting surfaces formed upon the valve housing block. The valve housing further includes an inlet port, an outlet port, and a sampling port each respectively formed in the valve housing block. The valve housing further includes an upstream passage which extends from the inlet port to the main flow valve mounting surface. The valve housing further includes a downstream passage which extends from the main flow valve mounting surface to the outlet port. The valve housing further includes a main flow weir which is disposed adjacent the main flow valve mounting surface between the upstream and downstream passages for controlling flow between the upstream and downstream passages. The valve housing further includes a primary passage which extends from the downstream passage to the sampling valve mounting surface. The valve housing further includes a secondary passage which extends from the sampling valve mounting surface and to the sampling port. The valve housing further includes a sampling weir which is disposed adjacent the sampling valve mounting surface between the primary and secondary passages for controlling flow between the primary and secondary passages. Importantly, the valve housing is positionable in a sterile access orientation with the sampling weir and lowermost portions of the downstream and primary passages being horizontally aligned. Further, the valve housing is positionable in a GMP orientation with the main flow weir and lowermost portions of the downstream and primary passages being horizontally aligned.
According to an embodiment of the present invention, the main flow weir is formed perpendicular to the sampling weir. The downstream passage has opposing first and second curved ends extending from the main flow weir adjacent the main flow valve mounting surface. The first curved end of the downstream passage is disposed along the lowermost portion of the downstream passage when the valve housing is in the GMP orientation. Further, the sampling weir is tangentially formed with the first curved end of the downstream passage. Similarly, the primary passage may have has opposing first and second curved ends extending from the sampling weir adjacent the sampling valve mounting surface. The first curved end of the primary passage is disposed along the lowermost portion of the primary passage when the valve housing is in the sterile access orientation. The main flow weir is tangentially aligned with the first curved end of the primary passage.
The valve housing block may be a rectangular body. In this regard, the valve housing block may have a front face and an opposing back faces. The main flow valve mounting surface may be formed upon the front face, and the sampling valve mounting surface may be formed upon the back face. The front and back faces may be parallel to one another. The valve housing block may further have opposing first and second end faces. The inlet port may be formed in the first end face, and the outlet port may be formed in the second end face. The first and second end faces may be formed orthogonal to the front and back faces. In addition, the valve housing block may have opposing third and forth end faces with the sampling port being formed in the third end face.
In one embodiment of the present invention, the downstream passage adjacent the main flow valve mounting surface is generally the same size as the primary passage adjacent the sampling valve mounting surface. In another embodiment of the present invention, the downstream passage adjacent the main flow valve mounting surface is sized smaller than the primary passage adjacent the sampling valve mounting surface.
As such, based on the foregoing, the present invention mitigates the inefficiencies and limitations associated with prior art arrangements. In particular, as mentioned above, the valve housing is positionable in a sterile access orientation with the sampling weir and lowermost portions of the downstream and primary passages being horizontally aligned. Such alignment allows for drainage of the downstream and primary passages. Further, the valve housing is positionable in a GMP orientation with the main flow weir and lowermost portions of the downstream and primary passages being horizontally aligned. Such alignment allows for drainage of the downstream and primary passages. In this regard, the integral sterile access/GMP valve housing of the present invention is specifically designed to allow for proper drainage of the downstream and primary passages in both the sterile access and GMP orientations. Such valve housing design avoids having to inventory two different valve housing parts in favor of a single dual purpose valve housing of the present invention. In addition, the sampling valve components are integrally formed with the main flow components. This not only avoids attachment fabrication steps of such structures as in the prior art, but also avoids usage of intermediate piping which creates an inherent dead-leg associated with such attachment. Accordingly, the present invention represents a significant advance in the art.